Means for clamping die blocks



Dec. 31, 1929. c. A. HUDSON MEANS FOR CLAMPING DIE BLOCKS 'Fi led March18, 1929 3 the ends of the block.

Patented Dec. 31, 1929 UNITE STATES CHAR-LES A. HUDSON, or ELLISBURG,

NEW YORK, ASSIGNOR TO F. E. HUDSON & SONS,

INCORPORATED, OF ELLISBURG, NEW YORK, A CORPORATION OF NEW YORK MEANSFOR CLAMPING DIE BLOCKS Application filed March 18, 1929. Serial No.347,932.

This invention relates to built-up Wooden die-blocks, designed for usein connection with clicking machines, and the like, for cutting leatherand other sheet materials, and has 5 for its object to provide a blockcomposed of a number of similar segments whose abutting sides areusually glued to each other, and wherein the joints and grain of thewood extend from top to bottom of the block.

These composite blocks are invariably bound by external iron straps orbars, which are mounted in a common plane upon the upright sides andends, and are held in place and given suitable tension by bolts orequivalent adjustable means. According to common practice, theseclamping irons extend respectively the full length of the sides andends, and interlock or otherwise join each other only at. the fourcorners of the block, and

when the bolts are drawn tight, the irons exert their greatest pressureat the corners, while their medial portions tend to flex and bowoutwardly, thereby failing to equally reinforce all parts of the blocThis trouble has been remedied to some extent, by the more or lessexpensive and complicating expedient, of perforating the blockstransversely at frequent intervals, and then passing threaded rodsthrough the perforations and the longer irons,

to which nuts are applied for drawing the i irons tightly against theopposing side edges of the block. This still leaves the block withoutmeans for adequately clamping the medial portions of the transverseirons against Hence, when the block is subjected to severe stresses andshocks incidental to the operation of a die-press, the

ends of the block tend to split, and being with- 1 out effective meansfor holding the split por- 40 tions in place, the blocks must bediscarded,

or else rebuilt and reconditioned.

A particular object of the present invention is to eliminate thestraight full-length side and end clamping irons, and to substitutetherefor four angular irons of substantially the same size and shape,and therefore interchangeable. These irons preferably conform to theangularity of the four corners of the block, and are so proportionedthat the free ends of their arms may be disposed at or near thelongitudinal and transverse centers of the block, whether the blocks aresquare or oblong, the said ends being formed with outwardly projectinglugs, which are perforated to re ceive bolts or other couplings by whichacontinuous bond is effected. By disposing the coupling means midway ofthe length and breadth, instead of at the corners, of the block, thetightening of the four bolts draws the irons against the sides and ends,without danger of the irons flexing or bowing outwardly away from themedial portions of the block. The angular irons are all formed to acommon template, and each iron may be applied to either of the fourcorners of the block without requiring any alteration or readjustment.Ordinarily, the transverse reinforcing rods may be dispensed with, but asmaller number of such rods may be employed on the longer blocks, tosupplement the side arms of the irons and increase the factor of safety.

The various features and parts of the invention will be understood fromthedetailed description which follows, and by reference to theaccompanying drawings, in which- Figure 1 is a top plan View of thesectional rectangular die-block, showing'its top portion tapered; alsoshowing similar right-angle clamping irons embracing its four corners.Fig. 2 is a side elevation of the same. Fig. 3 is a side elevation of aplain unbeveled block, showing the angle irons disposed midway of theheight of the block. And Fig. 4 is a broken top plan View of the taperedblock, showing tension means interposed between the spaced clamping lugsat the sides and ends of the block.

In the'drawings, 2 represents the built-up die-block, which comprises anumber of transversely disposed wooden segments 2, the latter being ofuniform height and carefully jointed and glued together, to form a solidrectangular or square body, whose top corners at the sides and ends arepreferably beveled, as shown in Figs. 1 and 2, to provide a cuttingsurface of substantially less area than the bottom of the block,primarily to prevent the dies from chipping said corners and impairingthe block.

In practically all built-up wooden dieblocks of the character described,the gluing of the segments 2 does not effect a bonding that is powerfulenough to withstand the hard blows and high pressure of the dies duringthe cutting operations, and it has been the common practice tosupplement such adhesive bonding by mounting metal bars or straps on theupright sides and ends of the blocks. Peretofore, these bonding ironshave usually been straight, and slightly longer than the side and enddimensions of the blocks, the ends of said bars being formed or fittedwith screw threaded or other interlocking means, by which the retainingand clamping may be effected. As a general rule, die-blocks of thisclass have been formed with square-cut top and bottom corners, and theclamping irons have been usually disposed midway of the height of theblocks, as shown in Fig. 3, and when the blocks are redressed afterhaving been worn uneven by continuous cutting, these irons have eitherto be adjusted downwardly, in order to facilitate repeated redressing ofthe'upper face, or else the blocks are inverted and alternately worn andredressed until further conditioning is hindered by the proxim ity ofthe irons. WVhere the old straight irons are employed, the tightening ofthe bolts effect the greatest clamping pressure at or adjacent thecorners of the block, and the medial portions of the irons tend tospring away from the sides and ends ofthe'block, which leaves thelongitudinal and transverse centers thereof unprotected and liable tocrack or split, when the blocks aresubjected to the stresses and shocksproduced by the dies.

In the present case, angular irons, as 3, are substituted for thestraight clamping members, each of said irons having one long arm and ashort arm '(in case the blockis oblong), as 3 and 3, which respectivelyengage the sides and ends of the block. These irons are formed to acommon pattern or template, whose angularity conformsexactly to that ofthe four corners, as 2 of the block, and the irons 3 being alike in alltheir parts, may be interchangeably applied to the several corners 2.The free ends ofthe arms 33 aresimilarly bent outwardly to form lugs 3the latter beingperforated to receive bolts 4, by which thecorresponding arms of adjacent irons may be adjustably connected anddrawn towards each other, for tightly clamping the irons tothe sides andends of the block, as shown. Thelngs 3" are suitably spaced foraffording ample range of adjustment, as well as to provide in a simplemanner for readily and securely clamping the block to the bed of thedie-press. The bolts 4 are preferably threaded at both ends to receivenuts 5, by which the clamping and adjusting may be rendered moreeffective. The bolts 4 are normally spaced from the block, and when thenuts 5 are tightened up, the lugs spring slightly towards each other.

plained.

This tends to increase the clamping pressure intermediate the corners 2and prevents the irons from springing away from the block, as in thecase of the straight irons, as eX- This exertion of relatively greatpressure midway of the length and breadth of the block, renders itunnecessary to provide the usual transverse reinforcing rods, exceptonlyin case of blocks of extraordinary length, when rods, as 6, may beemployed for reinforcing the longer arms of the irons 3, as shown inFigs. 1 and 2.

Fig. 3 shows the block 2* mounted upon and secur d to the bed 7 of adie-press, bv a plurality of similar adjustable clamps, each comprisinga member 8, which is pivoted to the bed by a bolt 8, and a member 9,which is formed with a hook 9 that grips one of the bolts 4:, and isprovided with a lug'9 having a'perforation that receives a threadedportion 8 of member 8, to which a nut 8 may be applied for effectingtheclamping.

In Fig. 41, stiff springs 10 are mounted upon the bolts between one ofthe lugs 8 and the adjacent nut 5, to offer resilient resistance to theloosening of the nuts, but more,particularly to compensate for the usualexpansion and contraction of the block, due to changes of weather andother conditions. Bythe provision of the springs l0,'the great strainsexerted by the expanding of the segments will be absorbed by thesprings, and in case of contraction of the block, the relatively greattension of the springs when the nuts are properly tightened will holdthe segments from separating or splitting, without necessitating anyadditional adjustment of the clamping means.

Having thus described my invention, what e I claim is 1. In combination,a rectangular built-up die-block, a plurality of similar clamping irons,each iron being bent to conform to the angles of the corners of theblock, the 7 arms of said irons terminating respectively near thelongitudinal and transverse centers of the block and their free endsbeing formed with perforated lugs that .register with the lugsof theadjacent irons, and means coacting with the registering lugs forclamping said irons against thesides and ends of the block.

2. The combination with a segmental wooden die-block, of a plurality ofclamping irons adapted to be interchange-ably.mounted upon-the fourcorners of the block, said irons being conformed tothe angles of saidcorners, the arms of each iron adapted to-overlie a portion of onesideand one end of theblock, the free ends of said arms being formedwith perforated lugs, the lugs of the adjacent irons at the oppositesides and ends being spaced apart, and bolts piercin each pair of lugsfor drawing'the irons tightly against the corners and the intermediateportions of said sides and ends.

8. The combination With a rectangular dieblock, of a plurality ofL-shaped clamping irons adapted to be mounted in a common plane upon theupright sides and ends of the block, each of said irons being formedwith one long and one short arm adapted to partially overlierespectively one side and one end of the block, the free ends of thearms being bent outwardly and perforated, the corresponding perforatedends of the adjacent irons being juxtaposited at the longitudinal andtransverse centers of the block and screw-threaded means for adjustablyconnesting said perforated ends and for clamping the irons throughoutthe length and breadth of the block.

In testimony whereof I afiix my signature.

CHARLES A. HUDSON.

